0ConnectionFactory.java

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package cdvirtualserver;

import java.sql.*;
import java.util.Vector;

/**
 *
 * @author Chayan-Dhaddha
 */
public class ConnectionFactory {
    
    Connection con;
    Statement stmt;
    private ConnectionFactory(){
        try{
            Class.forName("com.mysql.jdbc.Driver");
            con=DriverManager.getConnection("jdbc:mysql://localhost/virtualclass_db","root","");
            stmt=con.createStatement();
        }catch(Exception ex){
            System.out.println("Exception in db create...");
        }
    }
    private static ConnectionFactory conn;
    static {
        conn=new ConnectionFactory();
    }

    public static ConnectionFactory getInstance(){
        return conn;
    }
    public  int setData(String query)throws Exception{
        
        int n=stmt.executeUpdate(query);
        return n;
    }
    
    public  ResultSet getResultSet(String query)throws Exception{
        
        ResultSet rs=stmt.executeQuery(query);
        return rs;
    }     
    public  Vector<Vector> getData(String query)throws Exception{
       
        ResultSet rs=stmt.executeQuery(query);
        ResultSetMetaData rsmd=rs.getMetaData();
        int col=rsmd.getColumnCount();
        Vector<Vector> main=new Vector<Vector>();
        while(rs.next()){
             Vector<String> sub=new Vector<String>(); 
             for(int i=1;i<=col;i++)
                 sub.add(rs.getString(i));
             main.add(sub);
        }
        return main; 
        
    }
}